Erowid References Database
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Winkelhake JL, Voss EW.
“Studies on the Mechanism of Covalent Incorporation of a Lysergyl Derivative to Immunolobulin Peptides in Vitro”.
J.Biol.Chem.. 1975;250(6):2164-2172.
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Abstract
The covalent binding of d-lysergic acid diethylamide (LSD) to immunoglobulin peptides secreted by rabbit splenic lymphocytes was studied. Methods Hyperimmune splenic lymphocytes were obtained from New Zealand rabbits immunized with dinitrophenylated bovine gamma-globuIin or fluorescein-conjugated porcine gamma - globulin. Lymphocytes were cultured in minimal essential medium without leucine (L) or tryptophan (T) containing 3H-L or 14C-T and other additions as requied. IgG-synthesized by the cells was measured by radio-immunoassay. In binding studies, 3H-LSD was incubated with 80S-ribosomes or microsomes prepared from lymphocytes and binding assayed by equilibrium dialysis or by measuring radioactivity retained on the protein. LSD (Sandoz 0.01 to 10 mcg/ml), d-lysergic acid (LA, Sigma-Chem., to 100 mcg/ml) both inhibited incorporation of 14C-T into peptides secreted by lymphocytes. LSD and LA also increased the amount of peptides 'precipitated by anti-lysergyl antibody in a dose - dependent manner. The molecular weight of peptides secreted in the presence in the presence of LA was < 414500 daltons compared with > 67000 daltons in control lymphocytes. 3H-LSD was incorporated covalently into secreted peptides and this incorporation was inhibited by puromycin (P) and cyclohexirnide (CX, both Sigma-Chem.1 to 100 mcg/ml) in dose-dependent effects. Actino-mycin D (Sigma-Chem., 25-mcg/ml) did not-inhibit incorporation of 3H-L and 3H-LSD into trichloroacetic acid precipitable protein. No evidence was found for covalent binding of 3H-LSD to tRNA, but 3H-d-LSD-did bind to microsomes-and to 80S ribosomes from spleen cells. This binding was greater to ribosomes of immune than of non-immune spleen cells and was inhibited by 96% by LA (25mcg), by 99% by P (25 mcg), by 47% by CX (25 mcg), by 22% and 40% by deacylated tRNA from yeast and calf liver respectively and by only 4% by T (50 mcg). There were binding sites for d-LSD on each 80S ribosome and Ka for binding was 3.5 x l0^8M-1, Effects of LSD on translation and cellular protein synthesis are discussed. Attachment of the LSD derivative to peptides required active protein synthesis, but not RNA synthesis.
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